Here’s Single Coil’s opinions on nearly everything important about guitars. I’ve limited to 20 points, all of which should be accepted as Gospel. Trust ye the word of Single Coil on this folks, he knows what he’s saying.
Nobody wants to hear you solo for more than about three minutes. I don’t care HOW good you are. That’s just the way it is.
Maybe, maybe not. Depends on your audience. Depends how drunk your audience is. I have played places where a three minute solo is way waaayyyy to long, and I have played a solo for 15 minutes and the crowd was upset that it was too short. Other factors to consider are the Genre of music you are playing, your skill, your equipment, and your tone.